One day in 2011, Virginia Koerber, Lake Villa, Ill., recalled, she “woke up with a new life.” At 65, she got divorced.

“At an age when I had thought we’d travel and be retired, I was on my own,” she said.

People may marry with “forever” intentions, Koerber said, noting that her parents were married for 56 years, but “it doesn’t always turn out that way.”

Now, Koerber is part of a growing club: people who divorce after age 50. The divorce rate for this group doubled between 1990 and 2010, according to a study by the National Center for Family and Marriage Research at Bowling Green State University in Ohio.

“This surprised us, because the rate for younger people has leveled off,” said lead researcher Susan Brown, a sociology professor. “In 1990, only 1 in 10 divorces were people 50 and older. Now it’s 1 in 4.”

Brown attributes the increase to more seniors (“that huge segment of baby boomers”), more women with careers (“they don’t have to stay in empty-shell marriages for the money”) and more people ignoring their churches’ no-divorce rules.

Ironically, Brown said, some of the same factors that invigorate longtime marriages, such as children leaving home, cause others to end.

“The kids are gone, the marriage has been over for a while and one spouse decides she can’t take it anymore,” said James Pritikin, a Chicago-based lawyer and a fellow of the American Academy of Matrimonial Lawyers.

The over-50 divorce rate is even higher among those who remarried.

“They have a lot of complications because of stepchildren and financial and health care decisions,” Brown said. “But they also know they can divorce, that life goes on.”

Demographics affect late-in-life divorces, the study found. Blacks have the highest rates, followed by Hispanics, then whites and Asians. The more education, the lower the rate. The unemployed divorce more than workers do; retirees have the lowest rate.

Looking ahead, the study predicted that even if the over-50 divorce rate remains steady, the numbers of divorces will climb because of the aging population.

Society will be affected by the “graying of divorce,” Brown said. “We need to look at these people the way we’ve looked at widowhood. Many need help financially. They had fewer kids, and the kids aren’t always nearby, so they more often have to look outside the family for caregiving.”

The needs of divorcing clients past 50 are different from those of younger clients, Pritikin said.

“We have to make sure the ex has health insurance, which may mean getting COBRA (temporary health insurance) through her ex’s plan until she is eligible for Medicare,” he said. “The spouse who doesn’t have job skills may need (alimony). The most troubling part is the bulk of the marital estate is often tied up in home equity, but the home is worth less now or they’re underwater with their mortgage.”

Even among seniors, said Pritikin, age makes a difference in attitude.

“People in their 50s and 60s are ready to get on with their lives,” he said. “But the 80-year-old is angry. She’s going to be alone at a point when she didn’t expect this.”

The good news, Pritikin said, is society’s changing view of divorce.

“Used to be, you and your kids were tainted. Not now. The stigma is gone.”

Overall, Koerber considers herself lucky.

“My kids have their own lives, but they’re here for me if I need them,” she said. “My income is low, but at least I have a job and a house. I’m healthy. You know who my biggest support system is? Divorced girlfriends. We look out for each other.”